The Lezyne KTV Drive Headlight and KTV Pro Smart Taillight Set features Smart Connect allowing the headlight to control the taillight. Both lights can connect to and be controlled by a compatible Lezyne GPS computer. Features: Smart Connect technology Highly disruptive Daytime Flash mode Front - Max 200 lumens, up to 20 hour runtime depending on mode Rear - Max 75 lumens, up to 19.5 hour runtime depending on mode